1. Field of the Invention
The present invention relates to a field of determining a magnetic write width (MWW) of a head of a hard disc drive (HDD), and more particularly, to a method and apparatus to determine a magnetic write width of a head of an assembled hard disc drive.
2. Description of the Related Art
FIG. 1 shows a track profile to measure a magnetic write width of a head of a conventional hard disc drive (HDD). In FIG. 1, a vertical axis represents an output signal of a head and a horizontal axis represents a position of a track.
Conventionally, the magnetic write width of the head was measured before the hard disc drive was assembled. That is, the magnetic write width of the head is not measured during an assembled state of the hard disc drive. The magnetic write width of the head before assembling the hard disc drive is measured using a Guzik spinstand. As shown in FIG. 1, after a track profile is drawn, the magnetic write width is measured on the basis of a predetermined high threshold value and a predetermined low threshold value of the track profile. That is, tangents are drawn, which touch the track profile at a value corresponding to 50% of the average amplitudes in the track profile, thereby allowing the magnetic write width to be determined. In FIG. 1, a reference numeral 110 represents a magnetic write width, and a sum of ranges defined by reference numerals 120 and 130 represents a magnetic read width.
Since the magnetic write width is measured before assembling the hard disc drive according to the related art, the time for testing each of a hard disc drive's components increases, resulting in an increase of the hard disc drive's cost. Further, an adjacent track erase (ATE) feature and the measuring environment, as well as the magnetic write width, are factors that affect tracks adjacent to a target track while the HDD is operating. If the magnetic write width of the head is measured using only the profile of the target track, while disregarding the adjacent tracks, as in the related art, an error between the measured magnetic write width and the magnetic write width of the real HDD may occur.